Synthesis and properties of 1,3-bis[(2-bromo)benzene]triazene and its binuclear silver complex

The reaction of 2-bromoaniline with sodium nitrite affords a triazenido compound, 1,3-bis[(2-bromo)benzene]triazene (HL). Spectroscopic investigations show that HL bears a high selectivity for silver(I) ion in the presence of other metal ions. In the presence of Et3N, the reaction of HL and AgNO3 gives a binuclear triazenido-silver complex, [Ag2(L)2], which has been determined by X-ray diffraction analysis. Electrochemical studies show this silver complex can act as an electrocatalyst for hydrogen generation from neutral water with a turnover frequency (TOF) of 874.14 moles of hydrogen per mole of catalyst per hour (mol H2/mol catalyst/h) at an over potential (OP) of 837.6 mV.